[PATCH AUTOSEL 4.14 14/34] qed: Fix qed_ll2_post_rx_buffer_notify_fw() by adding a write memory barrier

Sasha Levin
2019-02-13T02:49:01Z

From: Denis Bolotin <dbolotin@marvell.com>

[ Upstream commit 46721c3d9e273aea880e9ff835b0e1271e1cd2fb ]

Make sure chain element is updated before ringing the doorbell.

Signed-off-by: Denis Bolotin <dbolotin@marvell.com>
Signed-off-by: Ariel Elior <aelior@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/qlogic/qed/qed_ll2.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/qlogic/qed/qed_ll2.c b/drivers/net/ethernet/qlogic/qed/qed_ll2.c
index b73bcbeb5f27..cef619f0ce10 100644
--- a/drivers/net/ethernet/qlogic/qed/qed_ll2.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_ll2.c
@@ -1487,6 +1487,10 @@ static void qed_ll2_post_rx_buffer_notify_fw(struct qed_hwfn *p_hwfn,
cq_prod = qed_chain_get_prod_idx(&p_rx->rcq_chain);
rx_prod.bd_prod = cpu_to_le16(bd_prod);
rx_prod.cqe_prod = cpu_to_le16(cq_prod);
+
+ /* Make sure chain element is updated before ringing the doorbell */
+ dma_wmb();
+
DIRECT_REG_WR(p_rx->set_prod_addr, *((u32 *)&rx_prod));
}

--
2.19.1